Protocol And Architecture For The Decentralization Of Content Delivery

ABSTRACT

Systems, methods, and devices of the various embodiments disclosed herein may provide a protocol and architecture for decentralization of content delivery. Various embodiments may provide a client based method for content delivery from content delivery networks (CDNs) via tiered caches of content hosted by Internet Service Providers (ISPs). In various embodiments, content delivery protocol (CDP) messages may enable clients to discover local cache network topologies and request content from a CDN based on a discovered local cache network topology. In various embodiments, security may be provided for the content delivery by the use of key encryption and/or file hashing.

RELATED APPLICATIONS

This application is a continuation of, and claims the benefit ofpriority to, U.S. Non-Provisional patent application Ser. No. 15/903,760entitled “Protocol And Architecture For The Decentralization Of ContentDelivery,” filed Feb. 23, 2018, which claims the benefit of priority toU.S. Provisional Patent Application 62/620,676 entitled “Protocol AndArchitecture For The Decentralization Of Content Delivery,” filed Jan.23, 2018, the entire contents of both of which are hereby incorporatedby reference for all purposes.

BACKGROUND

Conventional content delivery models represent a top-down centralizedapproach to content delivery, especially over-the-top (OTT) contentdelivery (e.g., OTT video delivery). Typically, a content deliverynetwork includes an origin server hosting a content item. Inconventional content delivery models, users access the origin server viaconnections between the user's respective computing devices and theorigin server established using an internet service provider (ISP)network. In conventional content delivery models, supporting this accessto the origin server places high demands on the ISP networks and thecost of delivering the content increases as more layers of the ISPnetwork are used to access the content in conventional content deliverymodels. Some conventional content delivery models reduce some of thedemand and costs of delivery content by using limited geographicallydistributed cache servers hosting copies of a content item, but the ISPnetworks gain only limited benefits in such conventional contentdelivery models as the ISP networks are typically still hauling bits ofthe content item through most layers of the ISP network.

SUMMARY

The systems, methods, and devices of the various embodiments disclosedherein may provide a protocol and architecture for decentralization ofcontent delivery. Various embodiments may provide a client based methodfor content delivery from content delivery networks (CDNs) via tieredcaches of content hosted by Internet Service Providers (ISPs). Invarious embodiments, content delivery protocol (CDP) messages may enableclients to discover local cache network topologies and request contentfrom a CDN based on a discovered local cache network topology. Invarious embodiments, security may be provided for the content deliveryby the use of key encryption and/or file hashing.

Various embodiments may provide a method for content delivery from aCDN, including sending a discovery message to an Internet ServiceProvider (ISP) network, receiving a capability response from a localcache server in response to the discovery message, wherein thecapability response indicates topology data for the local cache server,and sending a request for content to the CDN including the topology datafor the local cache server. Various embodiments may further includereceiving a response from the CDN including an address for the contentat the local cache server in response to sending the request for thecontent to the CDN, and sending a request for the content to the addressfor the content at the local cache server. Various embodiments mayfurther include receiving the content from the local cache server inresponse to the request for the content to the address for the contentat the local cache server, and sending a report to the CDN in responseto receiving the content from the local cache server. In variousembodiments, the discovery message may be a content delivery protocol(CDP) discovery message, the capability response may be a CDP capabilityresponse, the request for content to the CDN may be a CDP GET message,and/or the request for the content to the address for the content at thelocal cache server is an Hypertext Transfer Protocol (HTTP) GET message.In various embodiments, the topology data for the local cache server mayindicate tier cache server addresses in the ISP network. In variousembodiments, the topology data may be signed by a key of the CDN. Invarious embodiments, the response from the address for the content atthe local cache server may include a file name for the content that is ahash sum of the content. In various embodiments, the topology data mayindicate three different tier cache server addresses and the threedifferent tier cache server address may be at different levels of theISP network.

Further embodiments disclosed herein include a computing device having aprocessor configured with processor-executable instructions to performoperations of the methods summarized above. Further embodimentsdisclosed herein include a computing device including means forperforming functions of the methods summarized above. Furtherembodiments disclosed herein include a non-transitory processor-readablestorage medium having stored thereon processor-executable instructionsconfigured to cause a computing device processor to perform operationsof the methods summarized above. Further embodiments disclosed hereininclude a server configured with processor executable instructions toperform operations of the methods summarized above. Further embodimentsdisclosed herein include a server including means for performingfunctions of the methods summarized above. Further embodiments disclosedherein include a non-transitory processor-readable storage medium havingstored thereon processor-executable instructions configured to cause aserver processor to perform operations o of the methods summarizedabove.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and constitutepart of this specification, illustrate exemplary embodiments, andtogether with the general description given above and the detaileddescription given below, serve to explain the features of variousembodiments.

FIG. 1 is a system block diagram of a content delivery network (CDN)according to a conventional content delivery model.

FIG. 2 is a system block diagram illustrating interconnections between aCDN, Internet Service Provider (ISP) networks, and client computingdevices according to a conventional content delivery model

FIG. 3 is a system block diagram illustrating interconnections between aCDN, ISP networks, tier caches, and user computing devices according tovarious embodiments.

FIG. 4 is a block diagram illustrating content storage at tier cachesaccording to various embodiments.

FIG. 5A is a call flow diagram illustrating an embodiment method forcontent delivery.

FIG. 5B is a process flow diagram illustrating an embodiment method forcontent delivery.

FIG. 6 is a process flow diagram illustrating an embodiment method fortiered caching of content.

FIG. 7 is a process flow diagram illustrating an embodiment method fordetermining a local cache for content.

FIG. 8 is a component diagram of an example computing device suitablefor use with various embodiments.

FIG. 9 is a component diagram of an example server suitable for use withthe various embodiments.

DETAILED DESCRIPTION

The various embodiments will be described in detail with reference tothe accompanying drawings. Wherever possible, the same reference numberswill be used throughout the drawings to refer to the same or like parts.References made to particular examples and implementations are forillustrative purposes, and are not intended to limit the scope of theinvention or the claims.

As used herein, the terms “computing device” and “node” are usedinterchangeably herein to refer to any one or all of satellite or cableset top boxes, laptop computers, rack mounted computers, routers,cellular telephones, smart phones, personal or mobile multi-mediaplayers, personal data assistants (PDAs), personal computers, tabletcomputers, smart books, palm-top computers, desk-top computers, wirelesselectronic mail receivers, multimedia Internet enabled cellulartelephones, wireless gaming controllers, streaming media players (suchas, ROKU™), smart televisions, digital video recorders (DVRs), modems,and similar electronic devices which include a programmable processorand memory and circuitry for providing the functionality describedherein.

The various embodiments are described herein using the term “server” torefer to any computing device capable of functioning as a server, suchas communications server, a name server, a master exchange server, webserver, mail server, document server, database server, route server,content server, or any other type of server. A server may be a dedicatedcomputing device or a computing device including a server module (e.g.,running an application which may cause the computing device to operateas a server). A server module (e.g., server application) may be a fullfunction server module, or a light or secondary server module (e.g.,light or secondary server application) that is configured to providesynchronization services among the dynamic databases on computingdevices. A light server or secondary server may be a slimmed-downversion of server-type functionality that can be implemented on acomputing device thereby enabling it to function as a server only to theextent necessary to provide the functionality described herein.

FIG. 1 is a system block diagram of a content delivery network (CDN) 100according to a conventional content delivery model. The CDN 100 mayinclude an origin server 110 and CDN cache servers 120, 121, 122, and123. The origin server 110 may be connected to the CDN cache servers120, 121, 122, and 123, such as by a wired and/or wireless network, suchas the Internet, and via those connections the origin server 110 and CDNcache servers 120, 121, 122, and 123 may exchange data with one another.The origin server 110 may be located in one geographic region, such asin the continental United States, etc., and the CDN cache servers 120,121, 122, and 123 may be located within sub-regions within thatgeographic region, such as major metropolitan areas (e.g., New York, LosAngeles, etc.). The origin server 110 and/or CDN cache servers 120, 121,122, and 123 may interconnect with one or more Internet Service Provider(ISP) networks and may exchange data with the various devices of the ISPnetworks and/or client computing devices via the ISP networks. Theorigin server 110 and/or CDN cache servers 120, 121, 122, and 123 maystore copies of content, such as files (e.g., movies, audio clips,documents, etc.) or any other type data. The origin server 110 and/orCDN cache servers 120, 121, 122, and 123 may serve content to requestingcomputing devices. The requesting computing devices may send requestsfor the content to the origin server 110 and/or CDN cache servers 120,121, 122, and 123 via the respective ISP networks interconnected to theCDN 100. For example, client computing devices 103, 107, and 104 mayrequest content from CDN cache server 123 via the ISP networksassociated with client computing devices 103, 107, and 104 and CDN cacheserver 123 may serve the requested content to the client computingdevices 103, 107, and 104 by sending the content to the client computingdevices 103, 107, and 104 through their respective ISP networks. In thismanner, users 102, 108, and 106 may consume the content (e.g., playout avideo, view a document, listen to streamed audio, etc.) from the CDN 100at their respective client computing devices 103, 107, and 104.

FIG. 2 is a system block diagram illustrating interconnections betweenthe CDN 100, ISP networks ISP1 202 and ISP2 204, and client computingdevices 103, 107, and 104 according to a conventional content deliverymodel. With reference to FIGS. 1 and 2, ISP1 202 and ISP2 204 mayinclude various network pathways that represent hardware and/or softwareconnections between client computing devices on the ISP networks and theISP networks themselves. For example, client computing devices 103 and104 may connect to ISP network ISP1 202 and client computing device 107may connect to ISP network ISP2 204. The ISP networks ISP1 202 and ISP2204 may be arranged in tiered layers, such as core layers, distributionlayers, and access layers. Access layers may be the layers to whichclient computing devices connect and distribution layers may connectaccess layers to core layers. The cost associated with transportingcontent may grow as content is moved across more layers of the network.For example, the cost of carrying content at the core layer may be lowerthan the cost of carrying content from the core layer, through thedistribution layers, and across the access layers to the clientcomputing devices.

The ISP networks ISP1 202 and ISP2 204 may interconnect to the CDN 100.

The interconnects between the CDN 100 and the ISP networks ISP1 202 andISP2 204 may be physical connections via which data (e.g., messages,content, etc.) may be exchanged between devices of the CDN 100 (e.g.,origin server 110, CDN cache server 123, etc.) and the devices of, orconnected to, the ISP networks ISP1 202 and ISP2 204 (e.g., respectiveclient computing devices 103, 107, and 104, etc.).

While the CDN 100 may decentralize content among the origin server 110and CDN cache servers, such as CDN cache server 123, the interconnectsto the ISP networks ISP1 202 and ISP2 204 may result in minimal (e.g.,only one, two, three, etc.) actual physical connections between the CDN100 and the ISP networks ISP1 202 and ISP2 204 being available for theISP networks ISP1 202 and ISP2 204 to use to transport content from theCDN 100 to the client computing devices 103, 107, and 104. As thecontent from the CDN 100 is coming from the same minimal (e.g., onlyone, two, three, etc.) actual physical connections between the CDN 100and the ISP networks ISP1 202 and ISP2 204, the transport of thatcontent to the client computing devices 103, 107, and 104 incurs thefull cost of transporting content across the ISP networks ISP1 202 andISP2 204. In conventional content delivery models, supporting thisaccess to the CDN 100 places high demands on the ISP networks ISP1 202and ISP2 204 and the cost of delivering the content increases as morelayers of the ISP networks ISP1 202 and ISP2 204 are used to access thecontent in conventional content delivery models. Some conventionalcontent delivery models reduce some of the demand and costs of deliverycontent by using limited geographically distributed cache servershosting copies of a content item (e.g., CDN cache server 123, etc.).While this may reduce some cost to the CDN 100, the ISP networks ISP1202 and ISP2 204 gain only limited benefits in such conventional contentdelivery models as the ISP networks ISP1 202 and ISP2 204 are typicallystill hauling bits of the content item through most layers of the ISPnetworks ISP1 202 and ISP2 204.

Various embodiments may provide a protocol and architecture fordecentralization of content delivery that may reduce the demands andcosts placed on ISPs when compared to conventional content deliverymodels. Various embodiments may provide a client based method forcontent delivery from CDNs via tiered caches of content hosted by ISPs.Various embodiments may provide a decentralization of content deliverywhile still enabling an upstream (or backend) control of contentdelivery. Various embodiments may enable high data transfer rates and/orlow latency because content delivery may be decentralized to tieredcaches at the ISP network edges.

In various embodiments, content delivery protocol (CDP) messages mayenable client computing devices to discover local cache networktopologies and request content from a CDN based on a discovered localcache network topology. In various embodiments, CDP messages may providea secure transport protocol that uses Hypertext Transport Protocol(HTTP) as the underlying transport for content. In various embodiments,ISP networks may deploy tier cache servers at different layers of theISP networks. The tier cache servers may be “white box” servers that maybe configured to store copies of content provided by CDNs. For example,the tier cache servers may be Apache HTTP servers distributed atdifferent layers in ISP networks. In various embodiments, groupings oftier cache servers in the ISP networks may be associated together asbeing at different levels in the ISP networks. The grouping of tiercache servers in the ISP network at different levels may behierarchical. For example, tier cache servers closest to clientcomputing device connections in the network may be referred to as tier 1cache servers and, as tier cache servers are located deeper in thenetwork layers away from the client computing device connections, thetier cache servers may be referred to as tier 2, tier 3, tier 4, tier 5,etc. cache servers. Tier levels in the network may be directlyassociated to network layers or tier levels may be associated with morethan one network layer. ISP networks may include any number of tierlevels, such as one level, two levels, three levels, four levels, fivelevels, etc. As an example, different tier levels may be associated withcore layers, distribution layers, and access layers. Additionally,different tier levels may be associated with different level hubs and/orregional distribution centers in ISP networks.

FIG. 3 illustrates interconnections between the CDN 100, ISP networksISP1 202 and ISP2 204, tier cache servers 302, 304, and 306, and clientcomputing devices 103, 104, and 107 according to various embodiments.With reference to FIGS. 1-3, the tier cache servers 302, 304, and 306may be distributed throughout the ISP networks ISP1 202 and ISP2 204 inthree tiers, Tier 1, Tier 2, and Tier 3. For example, Tier 1 may includeone or more tier cache servers 302. The tier cache servers 302 may belocated within the ISP networks ISP1 202 and ISP2 204 closest to theclient computing devices 103, 104, and 107. Tier 2 may include one ormore tier cache servers 304 and Tier 3 may include one or more tiercache servers 306. The Tier 3 tier cache servers 306 may be locatedcloser to the interconnects to the CDN 100 in the ISP networks ISP1 202and ISP2 204 than the Tier 2 tier cache servers 304 which may be locatedbetween the Tier 3 tier cache servers 306 and Tier 1 tier cache servers302. In some embodiments, the number of Tier 1 tier cache servers 302may be greater than the number of Tier 2 and/or Tier 3 tier cacheservers 304 and/or 306. The tier cache servers 302, 304, and 306 mayexchange data with one another via connections in the ISP networks ISP1202 and ISP2 204 and may exchange messages according to various routingprotocols, such as the Border Gateway Protocol (BGP), etc., with oneanother to establish their respective hierarchies in the ISP networksISP1 202 and ISP2 204. In this manner, the tier cache servers 302, 304,and 306 may identify their respective topology data.

In various embodiments, the topology data may include one or moreaddresses, such as Internet Protocol (IP) Version (IPv) 4 (IPv4) and/or6 (IPv6) addresses of the tier cache servers 302, 304, and 306 reachablein the ISP networks ISP1 202 and ISP2 204. Topology data may alsoinclude capability information for the tier cache servers 302, 304, and306 reachable in the ISP networks ISP1 202 and ISP2 204, indications ofthe assigned tier level for the tier cache servers 302, 304, and 306reachable in the ISP networks ISP1 202 and ISP2 204, redundant tiercache server addresses (e.g., same tier level tier cache serveraddresses providing a back-up support to a tier cache server 302, 304,or 306), and/or any other information related to the tier cache servers302, 304, and 306 reachable in the ISP networks ISP1 202 and ISP2 204.Capability information may include supported version information, dockeror virtual machine information, etc. For example, a tier cache server302 in Tier 1 of ISP1 202 may identify the one or more tier cacheservers 304 that are reachable in Tier 2 of ISP1 202. In a similarmanner one of those reachable tier cache servers 304 in Tier 2 may haveidentified the one or more tier cache servers 306 that are reachable inTier 3 of ISP1 202. The tier cache server 304 in Tier 2 of ISP1 202 mayprovide its topology information, such as one or more address,capability information, assigned tier level, redundant tier cache serveraddress, etc., as well as may provide the topology information, such asone or more address, capability information, assigned tier level,redundant tier cache server address, etc., of the one or more tier cacheservers 306 that are reachable in Tier 3 of ISP1 202 to tier cacheserver 302 in Tier 1 of ISP1 202. In this manner, the topologyinformation for all tier levels may be distributed through the tiercache servers 302, 304, 306 of the different tier levels. Each tiercache server 302, 304, and 306 may use the topology information toindicate a path from that tier cache server 302, 304, and 306 up thevarious tiers 1, 2, and/or 3 in its respective ISP network ISP1 202and/or ISP2 204.

In various embodiments, the tier cache servers 302, 304, and 306 may bediscoverable via anycast messages. For example, a client computingdevice 103 connected to ISP1 202 may send an anycast message via itsconnections to the ISP1 202 to discover topology information fromreachable Tier 1 tier cache servers 302. The discovery message may be acontent delivery protocol (CDP) discovery message. A CDP discoverymessage may be an anycast discovery request indicating to a receivingnetwork node (e.g., a tier cache server) to provide topology data inresponse to the CDP discovery message. In response to receiving adiscovery request, such as a CDP discovery message, the receiving tiercache server 302, 304, or 306 may send a capability response indicatingtopology data, such as that tier cache server's 302, 304, or 306topology data and the topology data of any upstream and/or redundanttier cache servers 302, 304, or 306. The capability response may be aCDP capability response indicating topology data, such as one or moreaddress (e.g., IPv4, IPv6, etc.), capability information, assigned tierlevel, redundant tier cache server address, etc. Capability informationmay include supported version information, docker or virtual machineinformation, etc. Based on receiving the capability response from thetier cache server 302 of the ISP1 202, the client computing device 103may determine the path from the client computing device 103 through thereachable tier cache servers 302, 304, and 306 of the various tiers 1,2, and/or 3 in its respective ISP network ISP1 202. In variousembodiments, the closest reachable tier cache server to the clientcomputing device, such as tier cache server 302 to client computingdevice 103 may be referred to as a “local cache”. As an example, a localcache may be a tier cache server at the network edge level, such as atTier 1, from which client computing devices may receive CDP capabilityresponses indicating topology data.

In various embodiments, security may be provided for the contentdelivery by the use of key encryption. In various embodiments, thetopology data may be signed by a key of the CDN. For example, a publickey of the CDN and/or a public key of the tier cache server 302 may beuse by the tier cache server 302 providing the capability response togenerate a signature element using the public key of the CDN and/or thepublic key of the tier cache server 302 itself. This encrypted signatureelement may be added to the capability response along with the topologydata. The signature element may later be sent from a client computingdevice to the CDN 100 when requesting content. The CDN 100 may use theprivate key of the CDN and/or the private key of the tier cache server302 to attempt to decrypt the signature element. A successful decryptionof the CDN 100 may verify the topology data was received from anauthorized tier cache server and an unsuccessful decryption may indicatethe topology data was not received by an authorized tier cache server.

Various embodiments may enable content delivery from a CDN, such as CDN100 to client computing devices, such as client computing devices 103,104, 107 via tiered caches of content hosted by tier cache servers, suchas tier cache servers 302, 304, 306, of ISP network, such as ISPnetworks ISP1 202 and ISP2 204. In various embodiments, the CDN 100 maydistribute content to one or more tier levels, such as Tier 1, Tier 2,and/or Tier 3. In various embodiments, the content distributed to eachtier level may be different. The content distribution may vary based onattributes of the content, such as popularity (or demand) for thecontent (e.g., the most popular content may be distributed through themost tier levels and the least popular content may be only availablewithin the CDN 100 itself, etc.). The attributes of the content may bebased on the content itself, such as size, type, etc., and/or may bebased on the use of the content, such as demand (or popularity) asdetermined by usage reports (e.g., CDP reports, etc.) associated withthe content.

As an example, FIG. 4 illustrates content storage at tier levels withinISP1 202 according to various embodiments. With reference to FIGS. 1-4,the CDN 100 may have four items of content, such as files (e.g., movies,audio clips, documents, etc.) or any other type data, 402, 403, 404, and405 that the CDN 100 is making available to client computing devices,such as client computing device 103. Content 402 may be a highly popularitem of content (e.g., an episode of a hit television show, etc.), whilecontent 403, 403, and 405 may be successively less popular items ofcontent. The items of content 402, 403, 404, and 405 may be stored atthe origin server 110 and optionally one or more CDN cache servers 120,121, 122, and 123 of the CDN 100. The CDN 100 may determine the demandfor the content 402, 403, 404, and 405, and based on the demand for thecontent 402, 403, 404, and 405 may store one or more of the content 402,403, 404, and/or 405 at one or more of the tier cache servers 302, 304,and/or 306 at the various tier levels Tier 1, Tier 2, and/or Tier 3 inthe ISP network ISP1 202. For example, the highest demand content 402may be stored at tier cache servers 302, 304, and 306 of tier levelsTier 1, Tier 2, and Tier 3 in the ISP network ISP1 202. The next highestdemand content 403 may be stored at tier cache servers 304 and 306 oftier levels Tier 2 and Tier 3 in the ISP network ISP1 202. The thirdhighest demand content 404 be stored at tier cache servers 306 of tierlevel Tier 3 in the ISP network ISP1 202. The lowest demand content 405may be stored in the servers of the CDN 100 and not in the ISP networkISP1 202. In this manner, the highest demand content 402 may be pushedcloser to the ISP network ISP1 202 edge than the lower demand content403, 404, and 405. As the highest demand content 402 is closer to theclient computing device 103, the cost of providing the highest demandcontent 402 is lower than the cost would be if the highest demandcontent 402 were only available from the CDN 100. In variousembodiments, the storage of the content 402, 403, and 404 in the tiercache servers of the ISP network ISP1 202 may be governed by storageand/or service agreements between the CDN 100 network operator and theISP1 202 network operator. In various embodiments, the highest demandcontent 402 may be pushed to the local caches such that highest demandcontent 402 is available at tier cache servers at the network edgelevel.

In various embodiments, a client computing device, such as clientcomputing device 103, may request an item of content from the CDN 100,such as content 402. The request for content from the client computingdevice may be a CDP message including the topology data for the localcache server. For example, the computing device 103 may send a CDP GETmessage indicating the address of the tier cache server 302, tier cacheserver 304, and tier cache server 306 respectively in tier levels, Tier1, Tier 2, and Tier 3. The content may be selected by the computingdevice 103 based on browsing a website associated with the CDN 100,receiving a catalog file with content information, or in any othermanner. For example, the user 102 of the client computing device 103 maybrowse a video webpage associated with the CDN 100 and select the videothat is content 402 for output on the client computing device 103. Theclient computing device 103 may send a CDP GET message for the content402 to the CDN 100 and the CDP GET message may include the topology datafor the local cache server. In various embodiments, the CDP GET messagemay also include a signature element. The signature element may havebeen generated using the public key of the CDN 100 and/or the public keyof the tier cache server 302 that provided the capability response tothe client computing device 103. In some embodiments, the CDN 100 mayuse the private key of the CDN and/or the private key of the tier cacheserver 302 to attempt to decrypt the signature element. A successfuldecryption of the signature element may verify the topology data wasreceived from an authorized tier cache server and an unsuccessfuldecryption may indicate the topology data was not received by anauthorized tier cache server. Unsuccessful decryption may result in theCDN 100 rejecting or otherwise denying the request for content form theclient computing device.

In various embodiments, in response to receiving the request for contentfrom the client computing device, a device of the CDN 100, such as theorigin server 110, CDN cache server 123, or another device of the CDN100, may select the location from which the content may be served. As anexample, content may be served from the CDN 100. Serving content fromthe CDN 100 may be of most benefit when the CDN 100 is the only locationfor the content. For example, content 405 may be served from the CDN 100as it is not stored elsewhere. When content is to be served from the CDN100, the CDN 100 may directly respond to the request with the contentitem requested. As another example, content may be served from thevarious tier levels of the ISP1 202 when the requested content isavailable at tier cache servers of the ISP1 202. The CDN 100 may trackat which tier cache servers the content is stored in the ISP1 202 andmay designate which tier cache servers are to be used for transport ofcontent. As requests for content are received by the CDN 100, the CDN100 may determine which one or more tier cache server for a requesteditem of content are set for transport. The CDN 100 may compare thetopology data for the local cache server as indicated in the request(e.g., the CDP GET message) to the listing of tier cache servers set fortransport. Based on the comparison, the CDN 100 may select the lowesttier level of the tier cache servers set for transport as the tier cacheserver to provide the content. The CDN 100 may send a response, such asa CDP response, to the client computing device requesting the content.The response may include the address for the content at the tier cacheserver to provide the content. The client computing device may requestthe content at the address from the tier cache server. For example,client computing device 103 may request content 402 from the CDN 100 ina CDP GET message including the topology data for the local cacheserver, e.g., tier cache server 302. The CDN 100 may determine content402 is available at the local cache server (e.g., tier cache server 302)and may send a CDP response to the client computing device including theaddress, e.g., a Uniform Resource Locator (URL), of the content 402 atthe local cache server (e.g., tier cache server 302). The clientcomputing device 103 may send an HTTP GET message to the local cacheserver (e.g., tier cache server 302) requesting the content 402 and thelocal cache server (e.g., tier cache 302) may send the content 402 tothe client computing device 103.

Delivering content 402 from the tier cache server 302 closest to theclient computing device 103 (i.e., the tier cache server at the networkedge of the ISP1 202) may enable high data transfer rates and/or lowlatency because content delivery may be decentralized to the ISP networkedge. The high data transfer rates and/or low latency enabled by thevarious embodiments may enable various different applications for thedecentralization of content delivery. For example, tier cache serversmay operate as game servers to provide low latency game data to clientcomputing devices. As other examples, web browsers, HTTP servers, andOver-the-top (OTT) services may benefit from the high data transferrates and/or low latency enabled by the various embodiments. High datatransfer services/applications, such as virtual reality, autonomousvehicle network communications, etc., may utilize the decentralizationof content delivery enabled by the various embodiments to handle datatransfer and provide high data transfer rates and/or low latency.Additionally, firewall applications, network functions virtualizationapplications, and other commercial applications may utilize thedecentralization of content delivery enabled by the various embodimentsto handle data transfer and provide high data transfer rates and/or lowlatency.

While the various examples discussed above reference content 402 beingdelivered from the tier cache server closest to the client computingdevice, the CDN 100 may select other tier cache servers from which toprovide the content 402. For example, Tier 2 or Tier 3 cache server maybe indicated in the CDP response. In this manner, the CDN 100 maycontrol distribution of the content 402 and serve the content 402 fromany tier cache server in which the content 402 is stored.

In various embodiments, security may be provided for the contentdelivery by the use of file hashing. In various embodiments, theresponse from the address for the content at the local cache server mayinclude a file name for the content that is a hash sum of the content.The client computing device 103 may send an HTTP GET message to thelocal cache server (e.g., tier cache server 302) requesting the content402. The HTTP GET message may use the file name that is the hash sum ofthat requested content (i.e., 402). In response to receiving the content402, the client computing device 103 may generate a hash of the content402. For example, the client may use the content 402 as an input to thesame hash function used by the CDN 100 to generate the file name, andcompare the hash sum output to the file name that is the hash sumprovided in the CDP response. In response to the hash sums matching, theclient computing device 103 may determine that the content 402 is thecorrect content and/or that the content has not been altered. Inresponse to the hash sums not matching, the client computing device 103may determine that the received content is not the correct contentand/or that the content has been altered. In various embodiments, theclient computing device 103 may not output or otherwise use content thatis not the correct content and/or that the content has been altered.

In various embodiments, the client computing device may provide CDPreports to the CDN 100. The CDP reports may be sent from the clientcomputing device 103, 104, 107 to the CDN 100 in response to attempts todownload content, during the downloading of content, and/or uponcompletion of the download of the content. The CDP reports may report onvarious attributes of the download of the content, such as transferrate, error rate, latency, speed, data volume, throughput, bitrate, etc.As one example, the client computing device 103, 104, 107 may send a CDPprogress report to the CDN 100 indicating whether the request of thecontent from the local cache server (e.g., tier cache server 302) wassuccessful or not. As another example, the client computing device maysend a CDP progress report to the CDN 100 indicating attributes of thedownload of the content, such as transfer rate, error rate, latency,speed, data volume, throughput, bitrate, etc., from the local cacheserver (e.g., tier cache server 302). As a further example, when thedownload is complete, the client computing device 103, 104, 107 may senda CDP completion report to the CDN 100 indicating attributes of thedownload of the content, such as transfer rate, error rate, latency,speed, data volume, throughput, bitrate, etc., from the local cacheserver (e.g., tier cache server 302). Additionally, the CDP completionreport may indicate whether or not the check of the hash sum of the filename of the content was successful. One or more of the various CDPreports may be sent for each download/download attempt. For example,multiple CDP progress reports and a CDP completion report may be sentfor each download/download attempt. The CDN 100 may use the CDP reportsto monitor the performance of the tier cache servers being used to servecontent. As the CDN 100 may not directly control the tier cache servers,the CDN 100 may not receive telemetry or other performance data from thetier cache servers. The CDP reports may thus serve to give visibility ofthe provisioning performance of the tier cache servers to the CDN 100.The CDP reports and the resulting provisioning performance data may beused by the CDN 100 to control the provisioning of content from the tiercache servers. For example, based on the CDP reports content may bemoved up or down the tiers of the network and/or tier cache servers maybe brought on or off line at different network tiers.

FIG. 5A is a call flow diagram illustrating an embodiment method forcontent delivery. In various embodiments, the operations andinteractions illustrated in FIG. 5A may be performed by a processor of aCDN server, such as servers 110, 120, 121, 122, and 123, processors oftier cache servers, such as tier cache servers 302, 304, and 306, and aprocessor of a computing device, such as computing device 103, 104, and107.

With reference to FIGS. 1-5A, in operations 501 a local cache Tier 1tier cache server, such as a tier cache server 302, a Tier 2 tier cacheserver, such as a tier cache server 304, and a Tier 3 tier cache server,such as a tier cache server 306, may exchange data and/or messages withone another via various routing protocols, such as the Border GatewayProtocol (BGP), etc., to establish their respective hierarchies in anISP network, such as ISP networks ISP1 202 and ISP2 204. The Tier 1 tiercache server 302, Tier 2 tier cache server 304, and Tier 3 tier cacheserver 306 may store their respective hierarchies in the ISP network astopology data. In various embodiments, the topology data may include oneor more addresses, such as Internet Protocol (IP) Version (IPv) 4 (IPv4)and/or 6 (IPv6) addresses of the Tier 1 tier cache server 302, Tier 2tier cache server 304, and Tier 3 tier cache server 306 reachable in theISP network. Topology data may also include capability information forthe Tier 1 tier cache server 302, Tier 2 tier cache server 304, and Tier3 tier cache server 306, indications of the assigned tier level for theTier 1 tier cache server 302, Tier 2 tier cache server 304, and Tier 3tier cache server 306, redundant tier cache server addresses (e.g., sametier level tier cache server addresses providing a back-up support to atier cache server), and/or any other information related to the Tier 1tier cache server 302, Tier 2 tier cache server 304, and Tier 3 tiercache server 306. For example, the capability information may includesupported version information, docker or virtual machine information,etc. for one or more of the Tier 1 tier cache server 302, Tier 2 tiercache server 304, and Tier 3 tier cache server 306.

In operation 502, the CDN server, such as origin server 110, may receivean item of content, such as a media file, for provisioning to clientcomputing devices. In operation 503, the CDN server may determine one ormore tier level at which to store the item of content. For example, theCDN server may determine whether to store the item of content at one ormore of the Tier 1 tier cache server 302, Tier 2 tier cache server 304,and Tier 3 tier cache server 306. The content distribution may varybased on attributes of the content, such as popularity (or demand) forthe content (e.g., the most popular content may be distributed throughthe most tier levels and the least popular content may be only availablewithin the CDN 100 itself, etc.). In operation 504, the CDN server maysend a copy of the item of content to one or more of the Tier 1 tiercache server 302, Tier 2 tier cache server 304, and Tier 3 tier cacheserver 306. In various embodiments, the CDN server may assign a name tothe copy of the item of content at the one or more of the Tier 1 tiercache server 302, Tier 2 tier cache server 304, and Tier 3 tier cacheserver 306 that is a hash sum of the item of content. Optionally, theCDN server may also send a public key to the one or more of the Tier 1tier cache server 302, Tier 2 tier cache server 304, and Tier 3 tiercache server 306. The public key may be used by the Tier 1 tier cacheserver 302, Tier 2 tier cache server 304, and Tier 3 tier cache server306 to generate signature elements. The CDN server may set one or moreof the Tier 1 tier cache server 302, Tier 2 tier cache server 304, andTier 3 tier cache server 306 as the servers for transport of thecontent. In this manner, the CDN server may track both the tier cacheservers that receive copies of the items of content and which of thosetier cache servers should be used for provisioning of the content to anyrequesting client computing devices.

In operation 505, the client computing device, such as client computingdevice 103, may send an anycast message to the ISP network to discovertier cache servers and the topology information for those tier cacheservers. For example, the anycast message may a CDP discovery message. ACDP discovery message may be an anycast discovery request indicating toa receiving network node (e.g., a tier cache server) to provide topologydata in response to the CDP discovery message. In some embodiments,network edge tier cache servers, such as Tier 1 tier cache servers 302,also referred to as local cache servers, may be configured to listen forand respond to CDP discovery messages, while tier cache serversassociated with higher tiers may not be configured to listed for andrespond to CDP discovery messages.

In response to receiving a discovery request, the Tier 1 tier cacheserver 302 may send a capability response indicating topology data, suchas its respective topology data and the topology data of any upstreamand/or redundant tier cache servers, in operation 506. The capabilityresponse may be a CDP capability response indicating topology data, suchas one or more address (e.g., IPv4, IPv6, etc.), capability information,assigned tier level, redundant tier cache server address, etc. Based onreceiving the capability response from the Tier 1 tier cache server 302,the client computing device may determine the path from the clientcomputing device through the reachable tier cache servers of the varioustiers in its respective ISP network.

In operation 507, the client computing device may select a content itemfor downloading. The client computing device may select an item ofcontent by browsing a website, receiving a catalog file with contentinformation, or in any other manner. For example, the content item maybe the same content item received by the CDN server in operation 502.The client computing device may select content items for downloading inany manner. As one example, the client computing device may browse a webpage hosted by the CDN server (or another server associated with theCDN) listing content available for downloading. In various embodiments,the web page data, such as field elements of the web page, may indicatewhether or not the CDN server supports CDP requests.

In various embodiments, when the CDN server does not support CDPrequests, the client computing device may request selected content viaHTTP requests from the CDN server. In various embodiments, when the CDNserver supports CDP requests, the client computing device may generate arequest for an item of content, such as the item of content received bythe CDN server in operation 502. In operation 508 the client computingdevice may send a request for an item of content to the CDN server. Therequest for content from the client computing device may be a CDPmessage including the topology data for the local cache server. Forexample, the computing device may send a CDP GET message indicating theaddress of the Tier 1 tier cache server 302, Tier 2 tier cache server304, and Tier 3 tier cache server 306. In various embodiments, the CDPGET message may also include a signature element. The signature elementmay have been generated using the public key of the CDN server. Anexample CDP GET message schema may be as follows:

GET controller.example.com/video.file CDP/7.9

T2-Cache-IPv4: 10.10.10.25 10.10.10.26 T2-Cache-IPv6:2001:db8::10:25/128 T3-Cache-IPv4: 10.11.11.25 10.11.11.26IPv4-fed-Multicast: 10.10.10.25 Docker-Prefix: 2001:db8:0:111:111/64

Token=“PKI-SIGNED[<clientIP>:7843:<date>:broadband]”

The CDN server may receive the request, such as the CDP GET message, andin operation 509 the CDN server may determine from which to provisionthe requested item of content. For example, the requested item ofcontent may be available at the CDN server itself, the Tier 1 tier cacheserver 302, Tier 2 tier cache server 304, and/or Tier 3 tier cacheserver 306. In some embodiments, the CDN server may use the private keyof the CDN to attempt to decrypt the signature element. A successfuldecryption of the signature element may verify the topology data wasreceived from an authorized tier cache server and an unsuccessfuldecryption may indicate the topology data was not received by anauthorized tier cache server. Unsuccessful decryption may result in theCDN server rejecting or otherwise denying the request for content formthe client computing device. The CDN server may select the location fromwhich to provision the content in various manners. For example, when thecontent is only available at the CDN server, the CDN server may respondto the request by serving the requested item of content in response tothe request. As another example, when the content is stored at the CDNserver and one or more of the Tier 1 tier cache server 302, Tier 2 tiercache server 304, and Tier 3 tier cache server 306, the CDN server mayselect the tier cache server closest to the client computing device toserve the content. For example, the CDN server may compare the topologydata for the local cache server as indicated in the request (e.g., theCDP GET message) to the listing of tier cache servers set for transportstored at the CDN server. Based on the comparison, the CDN server mayselect the lowest tier level one of the tier cache servers set fortransport, such as Tier 1 tier cache server 302, as the tier cacheserver to provide the content.

In operation 510, the CDN server may send a response to the clientcomputing device including the address for the content at the tier cacheserver selected to provide the item of content. For example, theresponse may be a CDP response including a URL of the content at theTier 1 tier cache server 302, Tier 2 tier cache server 304, or Tier 3tier cache server 306. The URL may include the file name of the contentas it is stored at that tier cache server, and the file name may be ahash sum of the item of content. For example, a CDP response may includea URL for a file name that is a hash sum of an item of content stored atthe Tier 1 tier cache server 302.

In operation 511, the client computing device may send an HTTP GETmessage to the address for the content at the tier cache server selectedto provide the item of content. For example, the client computing devicemay send an HTTP GET message to the URL listed in the CDP response. Thetier cache server selected to provide the item of content may be one ofthe Tier 1 tier cache server 302, Tier 2 tier cache server 304, or Tier3 tier cache server 306. For example, the client computing device maysend an HTTP GET message to the Tier 1 tier cache server 302, which maybe the local cache server for the client computing device as it is thetier cache server closest to the network edge. Delivering content fromthe tier cache server closest to the client computing device may enablehigh data transfer rates and/or low latency because content delivery maybe decentralized to the ISP network edge. In operation 512, the tiercache server selected to provide the item of content may be one of theTier 1 tier cache server 302, Tier 2 tier cache server 304, or Tier 3tier cache server 306 may deliver the content to the client computingdevice. In response to receiving the content, the client computingdevice may generate a hash of the content. For example, the client mayuse the content as an input to the same hash function used by the CDNserver to generate the file name, and compare the hash sum output to thefile name that is the hash sum provided in the CDP response. In responseto the hash sums matching, the client computing device may determinethat the content is the correct content and/or that the content has notbeen altered. In response to the hash sums not matching, the clientcomputing device may determine that the received content is not thecorrect content and/or that the content has been altered. In variousembodiments, the client computing device may not output or otherwise usecontent that is not the correct content and/or that the content has beenaltered.

In various embodiments, the client computing device may provide CDPreports to the CDN server in operation 513. The CDP reports may be sentfrom the client computing device to the CDN server in response toattempting download of the content, during the downloading of content,and/or upon completion of the download of the content. The CDP reportsmay report on various attributes of the download of the content, such astransfer rate, error rate, latency, speed, data volume, throughput,bitrate, etc. As one example, the client computing device may send a CDPprogress report to the CDN server indicating whether the request of thecontent from the local cache server was successful or not. For example,a cache miss at a tier cache server may result in a CDP progress reportindicating the cache miss being sent to the CDN server. As anotherexample, the client computing device may send a CDP progress report tothe CDN server indicating attributes of the download of the content,such as transfer rate, error rate, latency, speed, data volume,throughput, bitrate, etc., from the local cache server. As a furtherexample, when the download is complete, the client computing device maysend a CDP completion report to the CDN server indicating attributes ofthe download of the content, such as transfer rate, error rate, latency,speed, data volume, throughput, bitrate, etc., from the local cacheserver. Additionally, the CDP completion report may indicate whether ornot the check of the hash sum of the file name of the content wassuccessful. One or more of the various CDP reports may be sent for eachdownload. For example, multiple CDP progress reports and a CDPcompletion report may be sent for each download.

In operation 514, the CDN server may use the CDP reports to monitor theperformance of the tier cache servers being used to serve content. Asthe CDN server may not directly control the tier cache servers, the CDNserver may not receive telemetry or other performance data from the tiercache servers. The CDP reports may thus serve to give visibility of theprovisioning performance of the tier cache servers to the CDN server.The CDP reports and the resulting provisioning performance data may beused by the CDN server to control the provisioning of content from thetier cache servers. For example, based on the CDP reports content may bemoved up or down the tiers of the network in operation 515.

FIG. 5B illustrates an embodiment method 550 for content delivery. Invarious embodiments, the operations of method 550 may be performed by aprocessor of a CDN server, such as servers 110, 120, 121, 122, and 123,processors of tier cache servers, such as tier cache servers 302, 304,and 306, and a processor of a computing device, such as computing device103, 104, and 107. In various embodiments, the operations of method 550may be performed in conjunction with one or more operations illustratedin FIG. 5A.

With reference to FIGS. 1-5B, in block 552 the client computing devicemay send a CDP discovery message to a local cache server and in block554 the local cache server may receive the CDP discovery message. A CDPdiscovery message may be an anycast discovery request indicating to areceiving network node (e.g., a tier cache server) to provide topologydata in response to the CDP discovery message. In some embodiments,local cache servers may be configured to listen for and respond to CDPdiscovery messages.

In block 556 the local cache server may send a CDP capability responseto the client computing device and in block 558 the client computingdevice may receive the CDP capability response. The CDP capabilityresponse may include topology data of the local cache server, such asone or more address (e.g., IPv4, IPv6, etc.), capability information,assigned tier level, redundant tier cache server address, etc. Based onreceiving the capability response from the local cache server, theclient computing device may determine the path from the client computingdevice through the reachable tier cache servers of the various tiers inits respective ISP network.

In block 560 the client computing device may browse and select content.The client computing device may select an item of content by browsing awebsite, receiving a catalog file with content information, or in anyother manner. As one example, the client computing device may browse aweb page hosted by the CDN server (or another server associated with theCDN) listing content available for downloading. In various embodiments,the web page data, such as field elements of the web page, may indicatewhether or not the CDN server supports CDP requests

In block 562 the client computing device may send a CDP GET with localcache capability information to the CDN server and in block 564 the CDNserver may receive the CDP GET with local cache capability information.The local cache capability information about the local cache server,such as the various supported versions, docker or virtual machinerequirements at the local cache server, etc. For example, an exampleschema may be as follows for a CDP GET indicating capability informationfor the local cache server:

GET controller.example.com/video.file { “current version” : [ “1.9.35” ]“fallback version” : [“1.7LTR, 1.0”] } } { “version” : [ “1.9.35”]T2-Cache-IPv4: 10.10.10.25 10.10.10.26 T2-Cache-IPv6: 2001 :db8::10:25/128 T3-Cache-IPv4: 10.11.11.25 10.11.11.26 } { “version” : [“1.0”] T2-Cache-IPv4: 10.10.10.25 10.10.10.26 T3-Cache-IPv4: 10.11.11.2510.11.11.26 }

As another example, an example schema may be as follows for a CDP GETindicating different capabilities of the local cache server for livevideo streaming in one version “1.9.36” while not in another version“1.9.35”:

GET controller.example.com/livevideo.feed { “current version” : [“1.9.36” ] “fallback version” : [“1.9.35, 1.7LTR, 1.0”] } } { “version”: [ “1.9.36”] T2-Cache-IPv4: 10.10.10.25 10.10.10.26 T2-Cache-IPv6:2001:db8::10:25/128 T3-Cache-IPv4: 10.11.11.25 10.11.11.26T1-Live-Video-Server-v4: “10.10.10.25 { Live-Method:Unicast-Fed-Multicast } } { “version” : [ “1.9.35”] T2-Cache-IPv4:10.10.10.25 10.10.10.26 T2-Cache-IPv6: 2001:db8::10:25/128T3-Cache-IPv4: 10.11.11.25 10.11.11.26 }

As another example, an example schema may be as follows for a CDP GETindicating different capabilities of the local cache server for livevideo streaming in one version “1.9.36” while not in another version“1.9.35:

GET controller.example.com/video.file { “current version” : [ “1.9.37” ]“fallback version” : [“1.9.34, 1.7LTR, 1.0”] } } { “version” : [“1.9.37”] T2-Cache-IPv4: 10.10.10.25 10.10.10.26 T2-Cache-IPv6:2001:db8:: 10:25/128 T3-Cache-IPv4: 10.11.11.25 10.11.11.26T1-Live-Video-Server-v4: “10.10.10.25 { Live-Method:Unicast-Fed-Multicast } Docker-container-support-IPv6: { “t2” : {“2001:1998:0:111:111::/64” } { “version” : [ “1.9.34”] T2-Cache-IPv4:10.10.10.25 10.10.10.26 T3-Cache-IPv4: 10.11.11.25 10.11.11.26 }

In determination block 566 the CDN server may determine whether thecontent is available at the local cache. For example, the requested itemof content may be available at the CDN server itself or the local cachebased on the demand for the content. The CDN server may compare the tier1 cache address listed in the CDP GET to a listing of where therequested content is stored to determine whether the content isavailable at the local cache. The tier 1 cache address being on thelisting of where the requested content is stored may indicate thecontent is available at the local cache. The tier 1 cache address nobeing on the listing of where the requested content is stored mayindicate the content is not available at the local cache.

In response to determining that the content is available at the localcache (i.e., determination block 566=(“Yes”), the CDN server may send aCDP response with a local cache URL for the content in block 568 and theclient computing device may receive the CDP response with the localcache URL for the content in block 570. The local cache URL may includea file name of the content that is a hash sum of the requested content.

In block 571 the client computing device may send a HTTP GET for thecontent to the local cache server and in block 572 the local cacheserver may receive the HTTP GET for the content. The HTTP GET may bedirected to the URL received in the CDP response. In block 574 the localcache server may send the content to the client computing device and inblock 576 the client computing device may receive the content. Inresponse to receiving the content, the client computing device maygenerate a hash of the content. For example, the client may use thecontent as an input to the same hash function used by the CDN server togenerate the file name, and compare the hash sum output to the file namethat is the hash sum provided in the CDP response. In response to thehash sums matching, the client computing device may determine that thecontent is the correct content and/or that the content has not beenaltered. In response to the hash sums not matching, the client computingdevice may determine that the received content is not the correctcontent and/or that the content has been altered. In variousembodiments, the client computing device may not output or otherwise usecontent that is not the correct content and/or that the content has beenaltered.

In block 578 the client computing device may send one or more CDPreports to the CDN server and in block 580 the CDN server may receivethe one or more CDP reports. The CDP reports may be sent from the clientcomputing device to the CDN server in response to attempting download ofthe content, during the downloading of content, and/or upon completionof the download of the content. The CDP reports may report on variousattributes of the download of the content, such as transfer rate, errorrate, latency, speed, data volume, throughput, bitrate, etc. As oneexample, the client computing device may send a CDP progress report tothe CDN server indicating whether the request of the content from thelocal cache server was successful or not. For example, a cache miss at atier cache server may result in a CDP progress report indicating thecache miss being sent to the CDN server. As another example, the clientcomputing device may send a CDP progress report to the CDN serverindicating attributes of the download of the content, such as transferrate, error rate, latency, speed, data volume, throughput, bitrate,etc., from the local cache server. As a further example, when thedownload is complete, the client computing device may send a CDPcompletion report to the CDN server indicating attributes of thedownload of the content, such as transfer rate, error rate, latency,speed, data volume, throughput, bitrate, etc., from the local cacheserver. Additionally, the CDP completion report may indicate whether ornot the check of the hash sum of the file name of the content wassuccessful. One or more of the various CDP reports may be sent for eachdownload. For example, multiple CDP progress reports and a CDPcompletion report may be sent for each download.

In response to determining that the content is not available at a localcache (i.e., determination block 566=“No”), in block 582 the CDN servermay send the content to the client computing device and in block 584 theclient computing device may receive the content.

FIG. 6 illustrates an embodiment method 600 for tiered caching ofcontent. In various embodiments, the operations of method 600 may beperformed by a processor of a CDN server, such servers 110, 120, 121,122, and 123, In various embodiments, the operations of method 600 maybe performed in conjunction with operations of method 550 of FIG. 5Band/or one or more operations illustrated in FIG. 5A.

With reference to FIGS. 1-6, in block 602 the CDN server may receivecontent for transport. The content may be data for download by clientcomputing devices. In block 604 the CDN server may determine demand forthe content. Demand for the content may be based on historicalinformation related to the content and/or similar types of content,based on usage reporting for the content, such as CDP reports, based onattributes of the content, based on predicted usage information relatedto the content and/or similar types of content, and/or based on anyother information associated with the content.

In determination block 606 the CDN server may determine whether thedemand supports tiered caching. For example, a demand threshold may seta minimum limit above which content much reach to qualify to be tiercached. Content with demand at or below the demand threshold may not betier cached and content with demand above the demand threshold may betier cached.

In response to determining that the demand supports tiered caching(i.e., determination block 606=“Yes”), in block 608 the CDN server maystore the content at one or more cache tiers. For example, based atleast in part on the demand, the content may be pushed to tiers closerto the network edge, such as with the highest demand content pushedthrough all tiers down to tier 1 tier cache servers and the lower demandcontent pushed to tier 2 and/or tier 3 cache servers, with the highestpredicted usage content pushed through all tiers down to tier 1 tiercache server and the lower demand content pushed to tier 2 and/or tier 3cache server, of in any other manner based on the demand and/or otherconsiderations.

In response to storing the content at one or more cache tiers or inresponse to determining that the demand does not support tiered caching(i.e., determination block 606=“No”), in block 610 the CDN server maystore the content at the CDN server. The method 600 may proceed to block604 to determine the demand for the content. In this manner, the demandmay be continually determined and storage at the cache tiers may beupdated as demand increases.

FIG. 7 is a process flow diagram illustrating an embodiment method fordetermining a local cache for content. In various embodiments, theoperations of method 700 may be performed by a processor of a CDNserver, such servers 110, 120, 121, 122, and 123, In variousembodiments, the operations of method 700 may be performed inconjunction with operations of methods 550 and/or 600 of FIGS. 5B and 6and/or one or more operations illustrated in FIG. 5A.

With reference to FIGS. 1-7, in block 701 the CDN server may receive CDPreports. The CDP reports may be sent from the client computing device tothe CDN server in response to attempting download of the content, duringthe downloading of content, and/or upon completion of the download ofthe content. The CDP reports may report on various attributes of thedownload of the content, such as transfer rate, error rate, latency,speed, data volume, throughput, bitrate, etc. As one example, the clientcomputing device may send a CDP progress report to the CDN serverindicating whether the request of the content from the local cacheserver was successful or not. For example, a cache miss at a tier cacheserver may result in a CDP progress report indicating the cache missbeing sent to the CDN server. As another example, the client computingdevice may send a CDP progress report to the CDN server indicatingattributes of the download of the content, such as transfer rate, errorrate, latency, speed, data volume, throughput, bitrate, etc., from thelocal cache server. As a further example, when the download is complete,the client computing device may send a CDP completion report to the CDNserver indicating attributes of the download of the content, such astransfer rate, error rate, latency, speed, data volume, throughput,bitrate, etc., from the local cache server. Additionally, the CDPcompletion report may indicate whether or not the check of the hash sumof the file name of the content was successful. One or more of thevarious CDP reports may be sent for each download. For example, multipleCDP progress reports and a CDP completion report may be sent for eachdownload.

In block 702 the CDN server may determine performance of the localcache. Performance of the local cache may be determined based at leastin part on transfer rate, error rate, latency, speed, data volume,throughput, bitrate, etc. In determination block 704 the CDN server maydetermine whether the local cache performance is below a minimumthreshold.

In response to determining that the local cache performance is below theminimum threshold (i.e., determination block 704=“Yes”), indetermination block 706 the CDN server may determine whether there is aredundant tier cache available. A redundant tier cache may be a tiercache in the same tier level and in the same ISP network that may be analternative to the current local cache for client computing devices inthat ISP network. In response to determining a redundant tier cache isavailable (i.e., determination block 706=“Yes”), in block 709 the CDNserver may set the redundant tier cache for transport. The redundanttier cache may be set for transport by the CDN server updating a tableor listing of tier cache servers to reflect that one or more items ofcontent are to be served from the redundant tier cache when a requestfor that content is received at the CDN server.

In response to determining a redundant tier cache is not available(i.e., determination block 706=“Yes”), in block 710 the CDN server mayset the next higher tier cache for transport. For example, when a tier 1local cache is not available, a tier 2 cache may be set for transport.The next higher tier cache may be set for transport by the CDN serverupdating a table or listing of tier cache servers to reflect that one ormore items of content are to be served from the next higher tier cachewhen a request for that content is received at the CDN server.

In response to determining that the local cache performance is at orabove the minimum threshold (i.e., determination block 704=“No”), indetermination block 708 the CDN server may determine whether the nextlower tier cache storing the content is available. The next lower tiercache storing the content may be a tier cache closer to the ISP networkedge than the currently set tier cache for transport. For example, whena tier 2 cache is set for transport, the CDN server may determine if atier 1 cache is available. In response to determining that the nextlower tier cache is available (i.e., determination block 708=“Yes”), inblock 710 the CDN server may set the next lower tier cache fortransport. The next lower tier cache may be set for transport by the CDNserver updating a table or listing of tier cache servers to reflect thatone or more items of content are to be served from the next lower tiercache when a request for that content is received at the CDN server

In response to setting a tier cache for transport in blocks 709, 710, or711 or in response to determining that the next lower tier cache is notavailable (i.e., determination block 708=“No”), the method 700 mayreturn to block 701. In this manner, as local cache performance maychange the tier caches set for transport may change as well.

Various embodiments illustrated and described are provided merely asexamples to illustrate various features of the claims. However, featuresshown and described with respect to any given embodiment are notnecessarily limited to the associated embodiment and may be used orcombined with other embodiments that are shown and described. Further,the claims are not intended to be limited by any one example embodiment.For example, one or more of the operations of the methods 550, 600, and700 may be substituted for or combined with one or more operations ofthe methods 550, 600, and 700 and vice versa.

The various embodiments (including, but not limited to, embodimentsdiscussed above with reference to FIGS. 1-7) described above may also beimplemented within a variety of computing devices, such as a laptopcomputer 810 as illustrated in FIG. 8. Many laptop computers include atouch pad touch surface 817 that serves as the computer's pointingdevice, and thus may receive drag, scroll, and flick gestures similar tothose implemented on mobile computing devices equipped with a touchscreen display and described above. A laptop computer 810 will typicallyinclude a processor 811 coupled to volatile memory 812 and a largecapacity nonvolatile memory, such as a disk drive 813 of Flash memory.The laptop computer 810 may also include a floppy disc drive 814 and acompact disc (CD) drive 815 coupled to the processor 811. The laptopcomputer 810 may also include a number of connector ports coupled to theprocessor 811 for establishing data connections or receiving externalmemory devices, such as a USB or FireWire® connector sockets, or othernetwork connection circuits (e.g., interfaces) for coupling theprocessor 811 to a network. In a notebook configuration, the computerhousing may include the touchpad 817, the keyboard 818, and the display819 all coupled to the processor 811. Other configurations of thecomputing device may include a computer mouse or trackball coupled tothe processor (e.g., via a USB input) as are well known, which may alsobe used in conjunction with the various embodiments.

Various embodiments (including, but not limited to, embodimentsdiscussed above with reference to FIGS. 1-7) may be implemented on anyof a variety of commercially available server devices, such as theserver device 900 illustrated in FIG. 9. Such a server device 900 mayinclude a processor 901 coupled to volatile memory 902 and a largecapacity nonvolatile memory, such as a disk drive 903. The server device900 may also include a floppy disc drive, compact disc (CD) or DVD discdrive 904 coupled to the processor 901. The server device 900 may alsoinclude network access ports 906 coupled to the processor 901 forestablishing data connections with a network connection circuit 905 anda communication network (e.g., IP network) coupled to othercommunication system network elements.

The processors 811, 901 may be any programmable microprocessor,microcomputer or multiple processor chip or chips that can be configuredby software instructions (applications) to perform a variety offunctions, including the functions of the various embodiments describedabove. In some devices, multiple processors may be provided, such as oneprocessor dedicated to wireless communication functions and oneprocessor dedicated to running other applications. Typically, softwareapplications may be stored in the internal memory before they areaccessed and loaded into the processors 811, 901. The processors 811,901 may include internal memory sufficient to store the applicationsoftware instructions. In many devices, the internal memory may be avolatile or nonvolatile memory, such as flash memory, or a mixture ofboth. For the purposes of this description, a general reference tomemory refers to memory accessible by the processors 811, 901 includinginternal memory or removable memory plugged into the device and memorywithin the processors 811, 901 themselves.

The foregoing method descriptions and the process flow diagrams areprovided merely as illustrative examples and are not intended to requireor imply that the steps of the various embodiments must be performed inthe order presented. As will be appreciated by one of skill in the artthe order of steps in the foregoing embodiments may be performed in anyorder. Words such as “thereafter,” “then,” “next,” etc. are not intendedto limit the order of the steps; these words are simply used to guidethe reader through the description of the methods. Further, anyreference to claim elements in the singular, for example, using thearticles “a,” “an” or “the” is not to be construed as limiting theelement to the singular.

The various illustrative logical blocks, modules, circuits, andalgorithm steps described in connection with the embodiments disclosedherein may be implemented as electronic hardware, computer software, orcombinations of both. To clearly illustrate this interchangeability ofhardware and software, various illustrative components, blocks, modules,circuits, and steps have been described above generally in terms oftheir functionality. Whether such functionality is implemented ashardware or software depends upon the particular application and designconstraints imposed on the overall system. Skilled artisans mayimplement the described functionality in varying ways for eachparticular application, but such implementation decisions should not beinterpreted as causing a departure from the scope of the presentinvention.

The hardware used to implement the various illustrative logics, logicalblocks, modules, and circuits described in connection with the aspectsdisclosed herein may be implemented or performed with a general purposeprocessor, a digital signal processor (DSP), an application specificintegrated circuit (ASIC), a field programmable gate array (FPGA) orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described herein. A general-purpose processor maybe a microprocessor, but, in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices,e.g., a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration. Alternatively, some steps ormethods may be performed by circuitry that is specific to a givenfunction.

In one or more exemplary aspects, the functions described may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored as one or moreinstructions or code on a non-transitory computer-readable medium ornon-transitory processor-readable medium. The steps of a method oralgorithm disclosed herein may be embodied in a processor-executablesoftware module and/or processor-executable instructions, which mayreside on a non-transitory computer-readable or non-transitoryprocessor-readable storage medium. Non-transitory server-readable,computer-readable or processor-readable storage media may be any storagemedia that may be accessed by a computer or a processor. By way ofexample but not limitation, such non-transitory server-readable,computer-readable or processor-readable media may include RAM, ROM,EEPROM, FLASH memory, CD-ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any other medium thatmay be used to store desired program code in the form of instructions ordata structures and that may be accessed by a computer. Disk and disc,as used herein, includes compact disc (CD), laser disc, optical disc,DVD, floppy disk, and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofnon-transitory server-readable, computer-readable and processor-readablemedia. Additionally, the operations of a method or algorithm may resideas one or any combination or set of codes and/or instructions on anon-transitory server-readable, processor-readable medium and/orcomputer-readable medium, which may be incorporated into a computerprogram product.

The preceding description of the disclosed embodiments is provided toenable any person skilled in the art to make or use the presentinvention. Various modifications to these embodiments will be readilyapparent to those skilled in the art, and the generic principles definedherein may be applied to other embodiments without departing from thespirit or scope of the invention. Thus, the present invention is notintended to be limited to the embodiments shown herein but is to beaccorded the widest scope consistent with the following claims and theprinciples and novel features disclosed herein.

What is claimed is:
 1. A method for content delivery from a content delivery network (CDN), comprising: sending, from a processor of a computing device, a discovery message to an Internet Service Provider (ISP) network; receiving, at the processor of the computing device, a capability response from a local cache server in response to sending the discovery message, wherein the capability response indicates topology data for the local cache server and the topology data is signed by a key of the CDN; and sending, from the processor of the computing device, a request for content to the CDN including the topology data for the local cache server.
 2. The method of claim 1, further comprising: receiving, at the processor of the computing device, a response from the CDN including an address for the content at the local cache server in response to sending the request for the content to the CDN; and sending, from the processor of the computing device, a request for the content to the address for the content at the local cache server.
 3. The method of claim 2, further comprising: receiving, at the processor of the computing device, the content from the local cache server in response to the request for the content to the address for the content at the local cache server; and sending, from the processor of the computing device, a report to the CDN in response to receiving the content from the local cache server.
 4. The method of claim 3, wherein: the discovery message is a content delivery protocol (CDP) discovery message; the capability response is a CDP capability response; the request for content to the CDN is a CDP GET message; and the request for the content to the address for the content at the local cache server is an Hypertext Transfer Protocol (HTTP) GET message.
 5. The method of claim 1, wherein the topology data for the local cache server indicates tier cache server addresses in the ISP network.
 6. The method of claim 5, wherein the response from the address for the content at the local cache server includes a file name for the content that is a hash sum of the content.
 7. The method of claim 5, wherein the topology data indicates three different tier cache server addresses and the three different tier cache server address are at different levels of the ISP network.
 8. A device, comprising: a processor configured with processor-executable instructions to perform operations comprising: sending a discovery message to an Internet Service Provider (ISP) network; receiving a capability response from a local cache server in response to sending the discovery message, wherein the capability response indicates topology data for the local cache server and the topology data is signed by a key of a content delivery network (CDN); and sending a request for content to the CDN including the topology data for the local cache server.
 9. The device of claim 8, wherein the processor is configured with processor-executable instructions to perform operations further comprising: receiving a response from the CDN including an address for the content at the local cache server in response to sending the request for the content to the CDN; and sending a request for the content to the address for the content at the local cache server.
 10. The device of claim 9, wherein the processor is configured with processor-executable instructions to perform operations further comprising: receiving the content from the local cache server in response to the request for the content to the address for the content at the local cache server; and sending a report to the CDN in response to receiving the content from the local cache server.
 11. The device of claim 10, wherein the processor is configured with processor-executable instructions to perform operations such that: the discovery message is a content delivery protocol (CDP) discovery message; the capability response is a CDP capability response; the request for content to the CDN is a CDP GET message; and the request for the content to the address for the content at the local cache server is an Hypertext Transfer Protocol (HTTP) GET message.
 12. The device of claim 8, wherein the processor is configured with processor-executable instructions to perform operations such that the topology data for the local cache server indicates tier cache server addresses in the ISP network.
 13. The device of claim 12, wherein the processor is configured with processor-executable instructions to perform operations such that the response from the address for the content at the local cache server includes a file name for the content that is a hash sum of the content.
 14. The device of claim 12, wherein the processor is configured with processor-executable instructions to perform operations such that the topology data indicates three different tier cache server addresses and the three different tier cache server address are at different levels of the ISP network.
 15. A non-transitory processor-readable storage medium having stored thereon processor-executable instructions configured to cause a processor to perform operations, comprising: sending a discovery message to an Internet Service Provider (ISP) network; receiving a capability response from a local cache server in response to sending the discovery message, wherein the capability response indicates topology data for the local cache server and the topology data is signed by a key of a content delivery network (CDN); and sending a request for content to the CDN including the topology data for the local cache server.
 16. The non-transitory processor-readable storage medium of claim 15, wherein the stored processor-executable instructions are configured to cause a processor to perform operations further comprising: receiving a response from the CDN including an address for the content at the local cache server in response to sending the request for the content to the CDN; sending a request for the content to the address for the content at the local cache server; and receiving the content from the local cache server in response to the request for the content to the address for the content at the local cache server; and sending a report to the CDN in response to receiving the content from the local cache server.
 17. The non-transitory processor-readable storage medium of claim 16, wherein the stored processor-executable instructions are configured to cause a processor to perform operations such that: the discovery message is a content delivery protocol (CDP) discovery message; the capability response is a CDP capability response; the request for content to the CDN is a CDP GET message; and the request for the content to the address for the content at the local cache server is an Hypertext Transfer Protocol (HTTP) GET message.
 18. The non-transitory processor-readable storage medium of claim 15, wherein the stored processor-executable instructions are configured to cause a processor to perform operations such that the topology data for the local cache server indicates tier cache server addresses in the ISP network.
 19. A method for content delivery from a content delivery network (CDN), comprising: receiving, at a processor of a computing device, a capability response from a local cache server in response to sending a discovery message to an Internet Service Provider (ISP) network, wherein the capability response indicates topology data for the local cache server and wherein the topology data indicates one or more of tier cache server capability information, tier cache server assigned tier level, or redundant tier cache server addresses.
 20. A device, comprising: a processor configured with processor-executable instructions to perform operations comprising: receiving a capability response from a local cache server in response to sending a discovery message to an Internet Service Provider (ISP) network, wherein the capability response indicates topology data for the local cache server and wherein the topology data indicates one or more of tier cache server capability information, tier cache server assigned tier level, or redundant tier cache server addresses.
 21. A non-transitory processor-readable storage medium having stored thereon processor-executable instructions configured to cause a processor to perform operations, comprising: receiving a capability response from a local cache server in response to sending a discovery message to an Internet Service Provider (ISP) network, wherein the capability response indicates topology data for the local cache server and wherein the topology data indicates one or more of tier cache server capability information, tier cache server assigned tier level, or redundant tier cache server addresses. 